rotate: promote k8s + mongo to LIVE-VM via real-target POCs

Ran live cutover POCs in the sandbox VM against the real target software and promoted both drivers from MOCK-ONLY to LIVE-VM in the proof table (data, not driver behaviour): - k8s: proven against real k3s v1.35 kube-apiserver + token controller (lab-provision-k8s.sh). The real apiserver serves a self-signed cert, so the driver gained CA-pinned TLS — blob params ca= (base64 PEM, pinned as the only trusted root) and insecure=1 (lab-only escape hatch), routed through a new clientFor(cr). Neither is test-awareness; a real deployment configures the same CA. Added TestK8sTLSTrust covering CA-pinned / insecure / untrusted-rejection and the blob round-trip. - mongo: proven against real mongod 8.0 (lab-provision-mongo.sh). npm stays MOCK-ONLY by decision (registry.npmjs.org not self-hostable; real create-token requires the account password in the body) — documented as a contract gap rather than faking a LIVE-VM. gcp/twilio/flyio remain MOCK-ONLY. Live POCs surfaced real-target-only behaviour now recorded in the docs: the apiserver's ~10s successful-auth cache (old token kept working ~7s after Secret deletion) and real mongosh's stdout prompt. Full suite 104 green, -race clean. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-06-18 21:50:21 -07:00
parent 35f19c007a
commit 9109da7ae4
5 changed files with 160 additions and 35 deletions
@@ -3,6 +3,8 @@ package rotate
 import (
 	"bytes"
 	"context"
+	"crypto/tls"
+	"crypto/x509"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
@@ -32,6 +34,10 @@ import (
 //   - sa=      the ServiceAccount name (the new Secret is annotated to it).
 //   - secret=  the token Secret's name — required to DELETE the old token.
 //   - token=   the bearer token value (rotated).
+//   - ca=      OPTIONAL base64(std) of the cluster CA PEM bundle. A real apiserver
+//              serves a self-signed cert, so the driver pins this CA as the only
+//              trusted root for the TLS handshake. Omit for a loopback emulator.
+//   - insecure=1  OPTIONAL escape hatch: skip TLS verification entirely (lab only).
 //
 // AUTH: every call authenticates with a token Bearer header against the apiserver. The
 // rotating SA needs RBAC to create/delete Secrets in its namespace. The new token is
@@ -53,20 +59,44 @@ func (k *K8s) Name() string { return "k8s" }
 // Detect claims credentials tagged Source == "k8s".
 func (k *K8s) Detect(c discover.Credential) bool { return c.Source == "k8s" }

-func (k *K8s) client() *http.Client {
+// clientFor returns the HTTP client for a given credential. An injected client
+// (tests / explicit CA config) always wins. Otherwise it builds a 15s client whose
+// TLS trust is pinned to the credential's ca= bundle (a real apiserver's self-signed
+// cert), or with verification disabled when insecure=1 is set (lab only).
+func (k *K8s) clientFor(cr k8sCred) (*http.Client, error) {
 	if k.HTTPClient != nil {
-		return k.HTTPClient
+		return k.HTTPClient, nil
 	}
-	return &http.Client{Timeout: 15 * time.Second}
+	tlsCfg := &tls.Config{MinVersion: tls.VersionTLS12}
+	switch {
+	case cr.insecure:
+		tlsCfg.InsecureSkipVerify = true
+	case cr.ca != "":
+		pem, err := base64.StdEncoding.DecodeString(cr.ca)
+		if err != nil {
+			return nil, fmt.Errorf("k8s: decode ca bundle: %w", err)
+		}
+		pool := x509.NewCertPool()
+		if !pool.AppendCertsFromPEM(pem) {
+			return nil, fmt.Errorf("k8s: ca bundle contained no usable certificates")
+		}
+		tlsCfg.RootCAs = pool
+	}
+	return &http.Client{
+		Timeout:   15 * time.Second,
+		Transport: &http.Transport{TLSClientConfig: tlsCfg},
+	}, nil
 }

 // k8sCred is the parsed credential blob. None of its fields are ever logged.
 type k8sCred struct {
-	base   string // scheme://host:port
-	ns     string
-	sa     string
-	secret string // token Secret name
-	token  string
+	base     string // scheme://host:port
+	ns       string
+	sa       string
+	secret   string // token Secret name
+	token    string
+	ca       string // base64(std) cluster CA PEM bundle (optional)
+	insecure bool   // skip TLS verification (lab only)
 }

 func parseK8sCred(v *vault.Vault, h *vault.Handle) (k8sCred, error) {
@@ -89,7 +119,7 @@ func parseK8sCred(v *vault.Vault, h *vault.Handle) (k8sCred, error) {
 		return k8sCred{}, fmt.Errorf("k8s: secret has no apiserver host")
 	}
 	q := u.Query()
-	c := k8sCred{base: scheme + "://" + u.Host, ns: q.Get("ns"), sa: q.Get("sa"), secret: q.Get("secret"), token: q.Get("token")}
+	c := k8sCred{base: scheme + "://" + u.Host, ns: q.Get("ns"), sa: q.Get("sa"), secret: q.Get("secret"), token: q.Get("token"), ca: q.Get("ca"), insecure: q.Get("insecure") == "1"}
 	if c.ns == "" || c.sa == "" {
 		return k8sCred{}, fmt.Errorf("k8s: secret missing namespace or serviceaccount")
 	}
@@ -110,6 +140,12 @@ func (c k8sCred) build() string {
 		q.Set("secret", c.secret)
 	}
 	q.Set("token", c.token)
+	if c.ca != "" {
+		q.Set("ca", c.ca)
+	}
+	if c.insecure {
+		q.Set("insecure", "1")
+	}
 	u.RawQuery = q.Encode()
 	return u.String()
 }
@@ -132,8 +168,9 @@ type k8sSecretObj struct {
 	Data map[string]string `json:"data,omitempty"`
 }

-// do issues an authenticated apiserver request and returns the body for 2xx responses.
-func (k *K8s) do(ctx context.Context, method, urlStr, token string, body []byte) ([]byte, int, error) {
+// do issues an authenticated apiserver request and returns the body. The credential
+// carries the TLS trust config (ca=/insecure=) used to build the client.
+func (k *K8s) do(ctx context.Context, cr k8sCred, method, urlStr string, body []byte) ([]byte, int, error) {
 	var r io.Reader
 	if body != nil {
 		r = bytes.NewReader(body)
@@ -142,11 +179,15 @@ func (k *K8s) do(ctx context.Context, method, urlStr, token string, body []byte)
 	if err != nil {
 		return nil, 0, err
 	}
-	req.Header.Set("Authorization", "Bearer "+token)
+	req.Header.Set("Authorization", "Bearer "+cr.token)
 	if body != nil {
 		req.Header.Set("Content-Type", "application/json")
 	}
-	resp, err := k.client().Do(req)
+	cl, err := k.clientFor(cr)
+	if err != nil {
+		return nil, 0, err
+	}
+	resp, err := cl.Do(req)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -181,7 +222,7 @@ func (k *K8s) Rotate(ctx context.Context, c discover.Credential, v *vault.Vault)
 	obj.Metadata.Annotations = map[string]string{"kubernetes.io/service-account.name": cr.sa}
 	body, _ := json.Marshal(obj)

-	_, code, err := k.do(ctx, http.MethodPost, cr.secretsURL(""), cr.token, body)
+	_, code, err := k.do(ctx, cr, http.MethodPost, cr.secretsURL(""), body)
 	if err != nil {
 		return nil, fmt.Errorf("k8s: create token secret: %w", err)
 	}
@@ -203,7 +244,7 @@ func (k *K8s) Rotate(ctx context.Context, c discover.Credential, v *vault.Vault)
 // awaitToken polls the new Secret until its .data.token is present, decoding it.
 func (k *K8s) awaitToken(ctx context.Context, cr k8sCred, name string) (string, error) {
 	for attempt := 0; attempt < 10; attempt++ {
-		rb, code, err := k.do(ctx, http.MethodGet, cr.secretsURL(name), cr.token, nil)
+		rb, code, err := k.do(ctx, cr, http.MethodGet, cr.secretsURL(name), nil)
 		if err != nil {
 			return "", fmt.Errorf("k8s: read token secret: %w", err)
 		}
@@ -236,7 +277,7 @@ func (k *K8s) Verify(ctx context.Context, newSecret *vault.Handle, v *vault.Vaul
 		return err
 	}
 	saURL := cr.base + "/api/v1/namespaces/" + url.PathEscape(cr.ns) + "/serviceaccounts/" + url.PathEscape(cr.sa)
-	_, code, err := k.do(ctx, http.MethodGet, saURL, cr.token, nil)
+	_, code, err := k.do(ctx, cr, http.MethodGet, saURL, nil)
 	if err != nil {
 		return fmt.Errorf("k8s verify: %w", err)
 	}
@@ -257,7 +298,7 @@ func (k *K8s) RevokeOld(ctx context.Context, c discover.Credential, v *vault.Vau
 	if cr.secret == "" {
 		return fmt.Errorf("k8s revoke: old token has no recorded secret name — delete it manually (guided)")
 	}
-	_, code, err := k.do(ctx, http.MethodDelete, cr.secretsURL(cr.secret), cr.token, nil)
+	_, code, err := k.do(ctx, cr, http.MethodDelete, cr.secretsURL(cr.secret), nil)
 	if err != nil {
 		return fmt.Errorf("k8s revoke: %w", err)
 	}
@@ -6,8 +6,10 @@ import (
 	"encoding/base64"
 	"encoding/hex"
 	"encoding/json"
+	"encoding/pem"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"strings"
 	"sync"
 	"testing"
@@ -218,6 +220,56 @@ func TestK8sRevokeRequiresSecretName(t *testing.T) {
 	}
 }

+// TestK8sTLSTrust proves the ca=/insecure= plumbing actually drives the TLS
+// handshake when no client is injected (the real-apiserver path). The httptest
+// server serves a self-signed cert, so a default client rejects it; pinning its CA
+// or setting insecure=1 must make the same request succeed.
+func TestK8sTLSTrust(t *testing.T) {
+	v := vault.New()
+	defer v.Purge()
+	ctx := context.Background()
+	const ns, sa, tok = "labns", "labsa", "eyJtls0123"
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("/api/v1/namespaces/"+ns+"/serviceaccounts/", func(w http.ResponseWriter, r *http.Request) {
+		json.NewEncoder(w).Encode(map[string]any{"metadata": map[string]any{"name": sa}})
+	})
+	srv := httptest.NewTLSServer(mux)
+	defer srv.Close()
+	host := strings.TrimPrefix(srv.URL, "https://")
+
+	caPEM := pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: srv.Certificate().Raw})
+	caB64 := base64.StdEncoding.EncodeToString(caPEM)
+
+	verifyWith := func(blob string) error {
+		k := &K8s{} // NO injected client — exercises clientFor's real TLS path
+		h := v.Store([]byte(blob))
+		return k.Verify(ctx, h, v)
+	}
+
+	base := "k8s://" + host + "/?ns=" + ns + "&sa=" + sa + "&token=" + tok
+
+	if err := verifyWith(base); err == nil {
+		t.Error("untrusted self-signed cert should fail without ca=/insecure=")
+	}
+	if err := verifyWith(base + "&insecure=1"); err != nil {
+		t.Errorf("insecure=1 should skip verification: %v", err)
+	}
+	if err := verifyWith(base + "&ca=" + url.QueryEscape(caB64)); err != nil {
+		t.Errorf("pinned ca= should trust the server cert: %v", err)
+	}
+
+	// Blob round-trip: ca=/insecure= survive build()->parse().
+	cr := k8sCred{base: "https://" + host, ns: ns, sa: sa, token: tok, ca: caB64, insecure: true}
+	got, err := parseK8sCred(v, v.Store([]byte(cr.build())))
+	if err != nil {
+		t.Fatalf("round-trip parse: %v", err)
+	}
+	if got.ca != caB64 || !got.insecure {
+		t.Errorf("ca/insecure did not round-trip: ca-match=%v insecure=%v", got.ca == caB64, got.insecure)
+	}
+}
+
 func TestK8sRejectsBadSecret(t *testing.T) {
 	v := vault.New()
 	defer v.Purge()
@@ -54,6 +54,8 @@ var proofLevels = map[string]ProofLevel{
 	"wireguard": ProofLiveVM, // real wg          (lab-provision-wg.sh)
 	"gitea":     ProofLiveVM, // real Gitea       (lab-provision-gitea.sh)
 	"appsecret": ProofLiveVM, // real local files (lab-provision-appsec.sh)
+	"mongo":     ProofLiveVM, // real mongod 8.0  (lab-provision-mongo.sh)
+	"k8s":       ProofLiveVM, // real k3s v1.35   (lab-provision-k8s.sh)

 	// proven only against an emulator / mock:
 	"aws":        ProofMockOnly, // moto mock AWS in VM; real AWS never hit
@@ -63,12 +65,10 @@ var proofLevels = map[string]ProofLevel{
 	"cloudflare": ProofMockOnly, // httptest emulator; no self-host
 	"ghactions":  ProofMockOnly, // httptest emulator; no self-host
 	"gitlab":     ProofMockOnly, // httptest emulator; GitLab CE too heavy for the VM
-	"mongo":      ProofMockOnly, // fake-mongosh stub; real-MongoDB VM POC not yet run
 	"npm":        ProofMockOnly, // httptest emulator; real registry never hit
 	"gcp":        ProofMockOnly, // httptest emulator (real RS256 JWT signing); no self-host
 	"twilio":     ProofMockOnly, // httptest emulator; no self-host
 	"flyio":      ProofMockOnly, // httptest GraphQL emulator; no self-host
-	"k8s":        ProofMockOnly, // httptest apiserver emulator; real k3s POC not yet run
 }

 // ProofLevelOf returns the recorded proof level for a driver name. Unknown or